Practical Weight Loss Strategy: Stair Climbing for Efficient Fat Burning

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In summary, the conversation discusses the measurement of energy in Calories and joules, as well as the efficiency of the human body in converting energy from metabolizing fat into mechanical work. The question at hand is whether running up and down a flight of stairs as a form of exercise is a practical way to lose weight. The conversation also includes calculations to determine the number of times the person must run the stairs in order to burn 1 lb of fat.
  • #1
Jacob87411
171
1
I worked this out but I must of gone wrong somewhere

Energy is conventionally measured in Calories as well as in joules. One Calorie in nutrition is one kilocalorie, defined as 1 kcal = 4186 J. Metabolizing 1 g of fat can release 9.00 kcal. A student decides to try to lose weight by exercising. She plans to run up and down the stairs in a football stadium as fast as she can and as many times as necessary. Is this in itself a practical way to lose weight? To evaluate the program, suppose she runs up a flight of 100 steps, each 0.150 m high, in 61.5 s. For simplicity, ignore the energy she uses in coming down (which is small). Assume that a typical efficiency for human muscles is 20.0%. Therefore when your body converts 100 J from metabolizing fat, 20 J goes into doing mechanical work (here, climbing stairs). The remainder goes into extra internal energy. Assume that the student's mass is 56.0 kg.

(a) How many times must she run the flight of stairs to lose 1 lb of fat?
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First off, we have to convert. When 1 lb of fat is burned that is 453.592 g. Each gram of fat burned requires 9.00 kcal as the problem states which is equivalent to 37674 J. So to burn 1 g of fat you need to work off 37674 J so to burn 453.592 g of fat one must burn (453.592)(37674)=17088625 J.

Ok so to the physics:
W=Fd
The distance is the vertical distance going up the stairs which is 100(.15m)=15m.

I got confused on what the force should be, is it the force of gravity which would be 56(9.8)?

If so W=fd = (560)(15) = 8400 but only 1/5 of that work goes towards metabolizing fat so 1680 J per time up the stairs. Then you take the total amount of joules needed to be burned / 1680 and get a huge, unreasonable number..any help is appreciated
 
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  • #2
The force of gravity is 9.8 and not 56
 
  • #3
Its not the persons weight, mg? So the force per flight of stairs is W=fd=(9.8)*(15)

So the work to go up 1 flight of stairs = 29.4 J, and you need to burn17088625 J so 17088625/29.4 is the number of times she must go up the stairs, which equals 581,245?
 
  • #4
1/5 of that work goes towards mechanical work not metabolizing fat.
 
  • #5
The total fat used up is 5 times the energy used in doing mechanical work. This is coz 20% of used fat is used to generate energy to do mechanical work. So even the other 80% is also lost from the body.
 
  • #6
So the energy used in work going up the stairs * 5 is the amount of energy burnt on each run of the stair flight? So is the total amount she needs to burn in order to burn a lb of fat 17088625 J?
 
Last edited:
  • #7
vaishakh said:
The force of gravity is 9.8 and not 56

OUCH! w=mg. If m=56 kg, then w=56*9.8 N.

-Dan
 

What is stair climbing?

Stair climbing is a physical activity that involves moving up and down a set of stairs, typically for exercise or transportation purposes.

What are the benefits of stair climbing?

Stair climbing is a great form of cardiovascular exercise, which can improve heart health and stamina. It also helps strengthen leg muscles and can aid in weight loss. Additionally, using stairs instead of elevators or escalators can increase daily physical activity levels.

How many calories are burned while stair climbing?

The number of calories burned while stair climbing depends on factors such as weight, speed, and intensity. On average, a person weighing 155 pounds can burn about 10 calories per minute while stair climbing at a moderate intensity.

Is stair climbing better for physical fitness compared to other exercises?

Stair climbing is a highly effective form of exercise for improving cardiovascular health and muscle strength. However, it should not be the only form of exercise in a well-rounded fitness routine. It is important to also incorporate other types of exercise, such as strength training and flexibility exercises, for overall physical fitness.

Are there any risks associated with stair climbing?

Stair climbing can be a high-impact activity, so it may not be suitable for individuals with joint problems or injuries. It is important to start slowly and listen to your body to avoid overexertion. Additionally, those with heart or respiratory conditions should consult a doctor before starting a stair climbing exercise routine.

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